jpa建表多对多

pom.xml:

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 
　　　　　　http://maven.apache.org/xsd/maven-4.0.0.xsd">
   　　 <modelVersion>4.0.0</modelVersion>

    <groupId>cn.dy</groupId>
    <artifactId>springJpaManyToMany</artifactId>
    <version>1.0-SNAPSHOT</version>
    <properties>
        <spring.version>4.2.4.RELEASE</spring.version>
        <hibernate.version>5.0.7.Final</hibernate.version>
        <slf4j.version>1.6.6</slf4j.version>
        <log4j.version>1.2.12</log4j.version>
        <c3p0.version>0.9.1.2</c3p0.version>
        <mysql.version>5.1.6</mysql.version>
        <maven.compiler.source>1.8</maven.compiler.source>
        <maven.compiler.target>1.8</maven.compiler.target>
    </properties>
    <dependencies>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.12</version>
            <scope>test</scope>
        </dependency>
        <!--spring start-->
        <!--spring aop-->
        <dependency>
            <groupId>org.aspectj</groupId>
            <artifactId>aspectjweaver</artifactId>
            <version>1.6.8</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-aop</artifactId>
            <version>${spring.version}</version>
        </dependency>
        <!--spring aop-->
        <!--spring ioc-->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>${spring.version}</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context-support</artifactId>
            <version>${spring.version}</version>
        </dependency>


        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-beans</artifactId>
            <version>${spring.version}</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-core</artifactId>
            <version>${spring.version}</version>
        </dependency>
        <!--spring ioc-->
        <!--spring end-->
        <!--spring 对orm框架的支持包-->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-orm</artifactId>
            <version>${spring.version}</version>
        </dependency>
        <!--spring 对orm框架的支持包-->
        <!--hibernate start-->
        <!--hibernate 核心包-->
        <dependency>
            <groupId>org.hibernate</groupId>
            <artifactId>hibernate-core</artifactId>
            <version>${hibernate.version}</version>
        </dependency>
        <!--hibernate 对JPA实现的包-->
        <dependency>
            <groupId>org.hibernate</groupId>
            <artifactId>hibernate-entitymanager</artifactId>
            <version>${hibernate.version}</version>
        </dependency>
        <!--hibernate 验证包-->
        <dependency>
            <groupId>org.hibernate</groupId>
            <artifactId>hibernate-validator</artifactId>
            <version>5.2.1.Final</version>
        </dependency>
        <!--hibernate end-->
        <dependency>
            <groupId>c3p0</groupId>
            <artifactId>c3p0</artifactId>
            <version>${c3p0.version}</version>
        </dependency>
        <dependency>
            <groupId>log4j</groupId>
            <artifactId>log4j</artifactId>
            <version>${log4j.version}</version>
        </dependency>
        <dependency>
            <groupId>org.slf4j</groupId>
            <artifactId>slf4j-api</artifactId>
            <version>${slf4j.version}</version>
        </dependency>
        <dependency>
            <groupId>org.slf4j</groupId>
            <artifactId>slf4j-log4j12</artifactId>
            <version>${slf4j.version}</version>
        </dependency>

        <!--mysql的驱动包-->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>${mysql.version}</version>
        </dependency>
        <!--spring dataJpa  的坐标-->
        <dependency>
            <groupId>org.springframework.data</groupId>
            <artifactId>spring-data-jpa</artifactId>
            <version>1.9.0.RELEASE</version>
        </dependency>
        <!--spring 测试 的坐标-->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-test</artifactId>
            <version>${spring.version}</version>
        </dependency>
        <!-- el 标签  的坐标-->
        <dependency>
            <groupId>javax.el</groupId>
            <artifactId>javax.el-api</artifactId>
            <version>2.2.4</version>
        </dependency>
        <dependency>
            <groupId>org.glassfish.web</groupId>
            <artifactId>javax.el</artifactId>
            <version>2.2.4</version>
        </dependency>
        <!-- el 标签  的坐标-->
    </dependencies>

</project>

resources:
　　applicationContext.xml:
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:aop="http://www.springframework.org/schema/aop"
       xmlns:context="http://www.springframework.org/schema/context"
       xmlns:jdbc="http://www.springframework.org/schema/jdbc"
       xmlns:tx="http://www.springframework.org/schema/tx"
       xmlns:jpa="http://www.springframework.org/schema/data/jpa"

       xsi:schemaLocation="
            http://www.springframework.org/schema/beans
            http://www.springframework.org/schema/beans/spring-beans.xsd
            http://www.springframework.org/schema/aop
            http://www.springframework.org/schema/aop/spring-aop.xsd
            http://www.springframework.org/schema/context
            http://www.springframework.org/schema/context/spring-context.xsd
            http://www.springframework.org/schema/jdbc
            http://www.springframework.org/schema/jdbc/spring-jdbc.xsd
            http://www.springframework.org/schema/tx
            http://www.springframework.org/schema/tx/spring-tx.xsd
            http://www.springframework.org/schema/data/jpa
            http://www.springframework.org/schema/data/jpa/spring-jpa.xsd">
    <!--1 创建数据库的连接池-->
    <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
        <property name="password" value="root"/>
        <property name="user" value="root"/>
        <property name="jdbcUrl" value="jdbc:mysql://localhost:3306/spring_data?characterEncoding=utf-8"/>
        <property name="driverClass" value="com.mysql.jdbc.Driver"/>
    </bean>
    <!--2 工厂类对象-->
    <bean id="entityManagerFactory"
          class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
        <!--数据源-->
        <property name="dataSource" ref="dataSource"/>
        <!--实体类的扫描器-->
        <property name="packagesToScan" value="cn.dy.jpa.entity"/>
        <!--jpa配置供应商的适配器-->
        <property name="jpaVendorAdapter">
            <bean class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter">
                <!--      指定数据库类型-->
                <property name="database" value="MYSQL"/>
                <!--    是否自动创建数据库表-->
                <property name="generateDdl" value="true"/>
                <!-- 数据库方言 支持的特有语法-->
                <property name="databasePlatform" value="org.hibernate.dialect.MySQLDialect"/>
                <!--是否向控制台输出语句 update hibernate.hbm2ddl.auto-->
                <property name="showSql" value="true"/>

            </bean>
        </property>
         <property name="jpaProperties">
             <props>
                 <prop key="hibernate.hbm2ddl.auto">update</prop>
             </props>
         </property>
    </bean>
    <!--配置事物-->
    <bean id="transactionManager" class="org.springframework.orm.jpa.JpaTransactionManager">
        <property name="entityManagerFactory" ref="entityManagerFactory"/>
    </bean>
    <!--一般出现在sevice层  start-->
    <tx:advice id="txAdvice" transaction-manager="transactionManager">
        <tx:attributes>
            <tx:method name="save*" propagation="REQUIRED"/>
            <tx:method name="insert*" propagation="REQUIRED"/>
            <tx:method name="update*" propagation="REQUIRED"/>
            <tx:method name="delete*" propagation="REQUIRED"/>
            <tx:method name="get*" read-only="true"/>
            <tx:method name="find*" read-only="true"/>
            <tx:method name="*" propagation="REQUIRED"/>
        </tx:attributes>
    </tx:advice>
    <!--aop-->
    <aop:config>
        <aop:pointcut id="pointcut" expression="execution(* cn.dy.jpa.service.*.*(..))"/>
        <aop:advisor advice-ref="txAdvice" pointcut-ref="pointcut"/>
    </aop:config>
    <!--一般出现在sevice层 end-->

<!--    <context:component-scanspring base-package="cn.dy.jpa"></context:component-scan>-->
<!--  spring dataJpa 整合  dao-->
    <jpa:repositories base-package="cn.dy.jpa.dao"
                      transaction-manager-ref="transactionManager"
                      entity-manager-factory-ref="entityManagerFactory"/>

</beans>
entity:
　　SysUser主表：

package cn.dy.jpa.entity;

import javax.persistence.*;
import java.io.Serializable;
import java.util.HashSet;
import java.util.Set;

/**
 * author:dingyi
 * time:2019/8/21 0021 10:02
 */
@Entity
@Table(name = "sys_user")
public class SysUser implements Serializable {
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Id
    @Column(name="user_id")
    private long userId;
    @Column(name="username")
    private String username;
    @Column(name="password")
    private String password;
    /**
     * 配置用户到角色的多对多关系
     *      配置多对多的映射关系
     *          1.声明表关系的配置
     *              @ManyToMany(targetEntity = SysRole.class,cascade = CascadeType.ALL)  //多对多
     *                  targetEntity：代表对方的实体类字节码
     *          2.配置中间表（包含两个外键）
     *                @JoinTable
     *                  name : 中间表的名称
     *                  joinColumns：配置当前对象在中间表的外键
     *                      @JoinColumn的数组
     *                          name：外键名
     *                          referencedColumnName：参照的主表的主键名
     *                  inverseJoinColumns：配置对方对象在中间表的外键
     */
    @ManyToMany(targetEntity = SysRole.class,cascade = CascadeType.ALL)
    @JoinTable(name = "sys_user_role",
            //   joinColumns 当前表在中间表中的外键           参照当前表的主键字段
            joinColumns = {@JoinColumn(name = "userid", referencedColumnName = "user_id")},

            //    inverseJoinColumns 对方对象在中间表 的外键                     参照当前表的主键字段
            inverseJoinColumns = {@JoinColumn( name = "roleid", referencedColumnName = "role_id")}

    )
    private Set<SysRole> roles = new HashSet<>();

    public long getUserId() {
        return userId;
    }

    public void setUserId(long userId) {
        this.userId = userId;
    }

    public String getUsername() {
        return username;
    }

    public void setUsername(String username) {
        this.username = username;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }

    public Set<SysRole> getRoles() {
        return roles;
    }

    public void setRoles(Set<SysRole> roles) {
        this.roles = roles;
    }

    @Override
    public String toString() {
        return "SysUser{" +
                "userId=" + userId +
                ", username='" + username + '\'' +
                ", password='" + password + '\'' +

                '}';
    }
}

SysRole从表：

package cn.dy.jpa.entity;

import javax.persistence.*;
import java.io.Serializable;
import java.util.HashSet;
import java.util.Set;

/**
 * author:dingyi
 * time:2019/8/21 0021 10:02
 */
@Entity
@Table(name = "sys_role")
public class SysRole implements Serializable {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Column(name="role_id")
    private long roleId;
    @Column(name="role_name")
    private String rolename;
    @Column(name="memo")
    private String memo;

    @ManyToMany(mappedBy = "roles",fetch = FetchType.LAZY)//放弃维护权
    private Set<SysUser> users = new HashSet<>();

    @Override
    public String toString() {
        return "SysRole{" +
                "roleId=" + roleId +
                ", rolename='" + rolename + '\'' +
                ", memo='" + memo + '\'' +

                '}';
    }

    public long getRoleId() {
        return roleId;
    }

    public void setRoleId(long roleId) {
        this.roleId = roleId;
    }

    public String getRolename() {
        return rolename;
    }

    public void setRolename(String rolename) {
        this.rolename = rolename;
    }

    public String getMemo() {
        return memo;
    }

    public void setMemo(String memo) {
        this.memo = memo;
    }

    public Set<SysUser> getUsers() {
        return users;
    }

    public void setUsers(Set<SysUser> users) {
        this.users = users;
    }
}

dao层：
　　userdao：

package cn.dy.jpa.dao;

import cn.dy.jpa.entity.SysUser;
import org.springframework.data.jpa.repository.JpaRepository;
import org.springframework.data.jpa.repository.JpaSpecificationExecutor;

/**
 * author:dingyi
 * time:2019/8/21 0021 10:03
 */
public interface SysUserDao extends JpaRepository<SysUser,Long>, JpaSpecificationExecutor<SysUser> {
}

roledao:

package cn.dy.jpa.dao;

import cn.dy.jpa.entity.SysRole;
import org.springframework.data.jpa.repository.JpaRepository;
import org.springframework.data.jpa.repository.JpaSpecificationExecutor;

/**
 * author:dingyi
 * time:2019/8/21 0021 10:04
 */
public interface SysRoleDao extends JpaRepository<SysRole,Long>, JpaSpecificationExecutor<SysRole> {
}

test类：

import cn.dy.jpa.dao.SysRoleDao;
import cn.dy.jpa.dao.SysUserDao;
import cn.dy.jpa.entity.SysRole;
import cn.dy.jpa.entity.SysUser;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.test.annotation.Commit;
import org.springframework.test.annotation.Rollback;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
import org.springframework.transaction.annotation.Transactional;

/**
 * author:dingyi
 * time:2019/8/21 0021 11:52
 */
@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration("classpath:applicationContext.xml")
public class testManyToMany {
    @Autowired
    SysUserDao userDao;
    @Autowired
    SysRoleDao roleDao;
    @Test
    @Transactional
    @Commit
    public void addUserAndRole(){
        // 1创建用户
        SysUser sysUser = new SysUser();
         sysUser.setUsername("admin");
          sysUser.setPassword("123456");
        // 2创建  角色
         SysRole sysRole = new SysRole();
        sysRole.setRolename("管理员");
        sysRole.setMemo("权限");
        // 3 配置用户和角色之间的关系
        sysUser.getRoles().add(sysRole);
        sysRole.getUsers().add(sysUser);
        //4  把用户角色写入数据可
        userDao.save(sysUser);
        //roleDao.save(sysRole); //无需再写
    }

    @Test
    @Transactional
    @Commit
    public void addUserAndRole1(){
        // 1创建用户
        SysUser user = new SysUser();
        user.setUsername("林志玲");
        user.setPassword("123456");
        SysUser user1 = new SysUser();
        user1.setUsername("杨幂");
        user1.setPassword("123456");
        // 2创建  角色
        SysRole role = new SysRole();
        role.setRolename("演员");
        SysRole rol = new SysRole();
        rol.setRolename("女主脚");
        // 3 配置用户和角色之间的关系
        user.getRoles().add(role);
        user.getRoles().add(rol);

        user1.getRoles().add(rol);
        user1.getRoles().add(role);

          role.getUsers().add(user);
          role.getUsers().add(user1);
          rol.getUsers().add(user);

          rol.getUsers().add(user1);
        //4  把用户角色写入数据可
        userDao.save(user);
        userDao.save(user1);
    }
    /**
     * 删除操作
     *     在多对多的删除时，双向级联删除根本不能配置
     * 禁用
     * 如果配了的话，如果数据之间有相互引用关系，可能会清空所有数据
     */
    @Test
    @Transactional
    @Commit
    @Rollback(false)
    public void removeUserAndRole(){

        userDao.delete(1L);
        userDao.delete(2L);

    }
}